Adolph hamaio



UNITED STATES PATENT OFFICE ADOLPH HAMANN, OF GROSSENHAIN, SAXONY, GERMANY.

PROCESS OF RENDERING BILLIARD AND WRITING CHALK UNBREAKABLE.

SPECIFICATION forming part of Letters Patent No. 330,019, dated November 10, 1885.

Application filed July 27, 1885. Serial No. 172,817.

To all whom it may concern:

Be it known that I, ADOLPH HAMANN, of the town of Grossenhain, in the Kingdom of Saxony and German Empire, have invented certain new and useful Improvements in Processes for Rendering Billiard and Writing Chalk Unbreakable, of which the following is a specification.

My invention relates to aprocess for rendering billiard and writing chalk unbreakablethat is, to so treat the chalk-cubes generally used for chalking billiard-cues, chalk for writing on black-boards, and other purposes, so that the same are rendered unbreakable.

The frangibility and brittleness of the prepared chalk now employed for the abovenamed purposes has been long felt to be the greatest disadvantage the same possesses, and various schemes have been tried to overcome the difficulty-for instance, by inserting the chalk in elastic covers of india-rubberwhich are, however, very inconvenient with billiardchalk, and entirely prevent their being employed for writing-chalk.

This present invention renders it possible to treat the chalk in such manner that the same is rendered fully unbreakable and will not peel or spring in cutting, so that the ad vantages obtained by employing my process will be evident to all.

The method of carrying my process into operation is as follows: The washed chalk is formed in suitable formers to suit the special purpose for which itisintended, and after the so-formed pieces have become thoroughly dry, the same are coated on all sides with a very (No specimens.)

fluid oil-varnish or boiled linseed or other drying oil, which is allowed to slowly dry in. This treatment is repeated four or five times in intervals of about twenty-four hours,which is necessary in order to assure that the oil or varnish penetrates through the entire piece of chalk and becomes intimately connected with the same. The correct saturation can be at once detected in cutting the chalk by the evident softness of the same, which must be equable throughout the entire thickness of the said chalk. In order to retain this softness of the chalk, I prefer to provide the same, after their having been treated as above mentioned, with a coating of shellac or other suitable varnish.

What I claim, and desire to secure by Letters Patent, is

1. As a new article of manufacture, cubes or other pieces of chalk for chalking billiardcues, writing, and other purposes, which are rendered unbreakable by saturating such said chalk with fluid oil-varnish or boiled linseed or other drying oil, substantially as described.

2. The combination of the chalk prepared as claimed under claim 1, with a coating of shellac or other suitable varnish, substantially as described.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

ADOLPH HAMANN.

VVitn esses nun. SCHMIDT, CARL SCHRADER. 

